POS0118 ADDING HYDROXYCHLOROQUINE IN REFRACTORY OBSTETRIC APS: OBSTETRIC OUTCOMES IN 182 PREGNANCIES
Authors: M. Gerde, R. Mac Kenzie, D. Viola, C. Heer, J. Balparda, E. Beruti
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> Pregnancy complications in obstetric APS (OAPS) include recurrent early pregnancy loss, fetal death, or premature birth due to preeclampsia, intrauterine growth restriction or placental insufficiency. The standard of care (SC) with low dose aspirin (LDA) and heparin has dramatically improved obstetric results, however 20-30% still have adverse outcomes despite treatment. Retrospective studies have shown good results with the addition of Hydroxychloroquine (HCQ). HCQ may have a beneficial effect in APS due to its anti-inflammatory, immunomodulatory and antithrombotic properties. Recently, EULAR recommended its use in refractory cases. Previously, in a retrospective study we reported that the addition of HCQ in women with primary OAPS and a pregnancy failure with SC was associated with a higher rate of live births (97 vs 62%) and a lower frequency of pregnancy complications (8 vs 37%) compared with conventional treatment. In this new study we show obstetric results from a larger cohort of refractory OAPS patients treated with HCQ. <h3>Objectives</h3> To assess pregnancy outcomes in a large cohort of women with refractory OAPS treated with Hydroxychloroquine in addition to conventional treatment. <h3>Methods</h3> This was an observational, retrospective, single-center cohort study. We analyzed pregnancy outcomes in women with refractory primary OAPS (2004-2022) who received HCQ 400 mg + enoxaparin 60 mg + LDA in their subsequent pregnancies. <h3>Results</h3> We evaluated 182 pregnancies in one hundred and seventy- three women (21-51y) treated with the addition of HCQ and a previous failure with conventional treatment; 18,9% of them had triple antibodies positivity. Live birth rate was 94% (CI 95%: 89,5-96,5). Term deliveries occurred in 95% of the pregnancies, mean gestational age at birth was 38 weeks (28-39) and mean weight 3021g (915g-4300g). Sixty percent were cesarean sections and 40 % vaginal deliveries. Pregnancy complications occurred in 12 % of the pregnancies (CI 95%: 7,3-19,5). Early pregnancy losses before 10 weeks occurred in 6% of the pregnancies. There were no late fetal deaths. Six patients who presented mild cutaneous allergy had to interrupt HCQ and were excluded from the analysis. <h3>Conclusion</h3> These results add observational evidence in favor of using Hydroxychloroquine in refractory Obstetric APS patients until results from ongoing RCT are published. <h3>References</h3> [1]Tektonidou MG et al. EULAR recommendations for the management of antiphospholipid syndrome in adults. Ann Rheum Dis 2019 Oct;78(10):1296-1304. [2]Alijotas-Reig J et al. Pathogenesis, Diagnosis and Management of Obstetric Antiphospholipid Syndrome: A Comprehensive Review. J Clin Med 2022 Jan 28;11(3):675. [3]Gerde M et al. The impact of hydroxychloroquine on obstetric outcomes in refractory obstetric antiphospholipid syndrome. Thromb Res. 2021; 206:104-110. [4]Sciascia S et al. The efficacy of hydroxychloroquine in altering pregnancy outcome in women with antiphospholipid antibodies. Evidence and clinical judgment. Thromb. Haemost. 2016; 115: 285–290. [5]Ruffatti A et al. The efficacy and safety of second-line treatments of refractory and/or high risk pregnant antiphospholipid syndrome patients. A systematic literature review analyzing 313 pregnancies. Semin. Arthritis Rheum. 2021; 51: 28–35. <h3>Acknowledgements:</h3> NIL. <h3>Disclosure of Interests</h3> None Declared.